Lg Lan125hv Service Manual

Room Air Conditioner

SVC MANUAL(General)

MODEL : General Wall Mounted-Inverter Type

CAUTION

Before Servicing the unit, read the safety precautions in General SVC manual. Only for authorized service personnel.

Internal Use Only

http://biz.lgservice.com

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LGE Internal Use Only

CONTENTS

Part 1 General Information

1. Safety Precautions........................................................................................................4

2. Nomenclature ...............................................................................................................7

Part 2 Functions & Controls

1. List of Functions & Controls........................................................................................9

2. Basic Mode Controls .................................................................................................10

3. Special Mode Controls ...............................................................................................12

4. Utility Functions .........................................................................................................13

5. Protection Functions & Controls...............................................................................16

Air Conditioner Service Manual

Part 3 Test Run

1. Check before Test Run ...............................................................................................32

2. Test Run Flow chart ....................................................................................................33

3. Test Run Detail ............................................................................................................34

Part 4 Trouble Shooting Guide

1. 2-Way, 3-Way Valve ....................................................................................................36

2. Pumping Down ...........................................................................................................37

3. Evacuation (All amount of refrigerant leaked) ........................................................38

4. Gas Charging (After Evacuation) ..............................................................................39

5. Cycle Troubleshooting Guide ....................................................................................40

6. Electric Parts Troubleshooting Guide.......................................................................41

7. Self-diagnosis Function .............................................................................................46

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LGE Internal Use Only

Part 1 General Information

1. Safety Precautions ............................................................................................................4

2. Nomenclature......................................................................................................................7

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LGE Internal Use Only

Part 1 General Information

1. Safety Precautions

To prevent injury to the user or other people and property damage, the following instructions must be followed.

■ Incorrect operation due to ignoring instruction will cause harm or damage. The seriousness is classified by the following indications.

This symbol indicates the possibility of death or serious injury.

This symbol indicates the possibility of injury or damage to properties only.

■ Meanings of symbols used in this manual are as shown below.

Be sure not to do.

Be sure to follow the instruction.

Dangerous Voltage

1.1 Cautions in Repair

Be sure to disconnect the power cable plug from the plug socket before disassembling the equipment for a repair.Internal components and circuit boards are at main potential when the equipment is connected to the power cables. This high voltage is extremely dangerous and may cause death or severe injury if come in contact with it.

Do not touch the discharging refrigerant gas during the repair work. The discharging refrigerant gas.The refrigerant gas can cause frostbite.

Release the refrigerant gas completely at a well-ventilated place first. Otherwise, when the pipe is disconnected, refrigerant gas or refrigerating machine oil discharges and it Can cause injury.

When the refrigerant gas leaks during work, perform ventilation. If the refrigerant gas comes in contact with a fire, poisonous gas generates. A case of leakage of the refrigerant and the closed room full with gas is dangerous because a shortage of oxygen occurs. Be sure to perform ventilation.

When removing the front panel or cabinet, execute short-circuit and discharge between high voltage capacitor terminals. If discharge is not executed, an electric shock is caused by high voltage resulting in a death or injury.

Do not turn the air-conditioner ON or OFF by plugging or unplugging the power plug. There is risk of fire or electrical shock.

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LGE Internal Use Only

Part 1 General Information

Do not use a defective or underrated circuit breaker. Use the correctly rated breaker and fuse. Otherwise there is a risk of fire or electric shock.

Install the panel and the cover of control box securely. Otherwise there is risk of fire or electric shock due to dust, water etc.

Indoor/outdoor wiring connections must be secured tightly and the cable should be routed properly so that there is no force pulling the cable from the connection terminals. Improper or loose connections can cause heat generation or fire.

Do not touch, operate, or repaire the product with wet hands. Holding the plug by hand when taking out. Otherwise there is risk of electric shock or fire.

Do not turn on the breaker when the front panel and cabinet are removed.

Be sure to ground the air conditioner with an earthing conductor connected to the earthing terminal.

Conduct repair works after checking that the refrigerating cycle section has cooled down sufficiently. Otherwise, working on the unit, the hot refrigerating cycle section can cause burns.

Do not tilt the unit while removing panels. Otherwise, the water inside the unit can spill and wet floor.

Do not use the welder in a well-ventilated place. Using the welder in an enclosed room can cause oxygen deficiency.

Be sure to turn off power switch before connecting or disconnecting connector, or parts damage may be occur.

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LGE Internal Use Only

Part 1 General Information

1.2 Inspections after Repair

Check to see if the power cable plug is not dirty or loose. If the plug is dusty or loose it can cause an electrical shock or fire.

Do not use a joined power cable or extension cable, or share the same power outlet with other electrical appliances. otherwise, it can cause an electrical shock, excessive heat generation or fire.

Do not insert hands or other objects through the air inlet or outlet while the product is operating. There are sharp and moving parts that could cause personal injury.

Do not block the inlet or outlet of air flow. It may cause product failure

Check to see if the parts are mounted correctly and wires are connected. Improper installation and connections can cause an electric shock or an injury.

Check whether the installation platform or frame has corroded. Corroded installation platform or frame can cause the unit to fall, resulting in injury.

Be sure to check whether the earth wire is correctly connected.

After the work has finished, be sure to do an insulation test to check whether the resistance is 2[Mohm] or more between the charge section and the non-charge metal section (Earth position). If the resistance value is low, a disaster such as a leak or electric shock is caused at user’s side.

Check the drainage of the indoor unit after the repair. If drainage is faulty the water may enter the room and wet floor.

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LGE Internal Use Only

2. Nomenclature

2.1 Global Model Name

AS W1264GG1

12 - 345678910

Code Type Code of Model Meaning

1 Production Center, A~Z L: Chang-won R22

Refrigerant A: Chang-won R410A

2 Product Type A~Z S: Split Type Air Conditioner 3 Cooling/Heating/Inverter A~Z C: Cooling Only

H: Heat Pump X: C/O + E/Heater Z: H/P + E/Heater V: AC Inverter C/O N: AC Inverter H/P Q: DC Inverter C/O W: DC Inverter H/P

4, 5 Capacity 0~9 Cooling/Heating Capacity

Ex. "09" → 9,000 Btu/h

6 Electric Range 1~9 1: 115V/60Hz

A~Z 2: 220V/60Hz

3: 208-230V/60Hz 5: 200-220V/50Hz 6: 220-240V/50Hz 7: 110V, 50/60Hz

Part 1 General Information

7 Chassis A~Z Name of Chassis

8 Look A~Z Look,

Color (Artcool Model)

9, 10 Function A~Z

A Basic B Basic+4Way C Plasma Filter D Plasma Filter+4 Way E Tele+LCD F Tele+LCD+Nano plasma+4Way G NBF F+(A/changeove)+A/clean+Low A H NBF F+(A/changeove)+A/clean+4way+Low A

I Tele+LED+4way J Internet K Plasma F+4Way+Oxygen generator L NBF F+(A/changeove)+A/clean M NBF F+(A/changeove)+A/clean+4way N NBF F+(A/changeove)+A/clean+PTC P NBF F+(A/changeove)+Autoclean+4way+PTC Q NBF F+(A/changeove)+A/clean+4way+Low A+PTC R Negative ion+A/Clean S (Nano)Plasma+Negative ion+A/Clean T 4way+(Nano)Plasma F+Negative ion+A/Clean U

Nano Plasma F+4Way+(A/changeove)+A/clean+Oxygen generator

V

4way+(Nano)Plasma F+Negative ion+A/Clean+Oxygen generator

W Dry contact

Y Basic + Low A

11 Serial No. 1~9 LG Model Development Serial No.

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LGE Internal Use Only

Part 2 Functions & Controls

1. List of Controls & Functions ..........................................................................................9

2. Basic Mode Controls......................................................................................................10

3. Special Mode Controls...................................................................................................12

4. Utility Functions .............................................................................................................13

5. Protection Functions & Controls .................................................................................16

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LGE Internal Use Only

Part 2 Functions & Controls

1. List of Functions & Controls

Category Function Description Remark

Basic mode

controls

Special Mode

controls

Utility Functions

Protection Controls &

Functions

Cooling Mode Heating Mode Healthy Dehumidification Auto Changeover

Jet Cool Jet Heat Energy saving

Forced operation Auto Clean

Air volume control Natural Air control Chaos Swing Sleep mode Auto control

Auto Restart Function

Five Second Delay (Fan) Two Minutes Stand-by

(Comp.) Hot Start Freeze prevention Compressor Pre Heating Sump Heater Control Automatic Defrost Power Relay Control Inverter (with inverter

power control) Overheating Protection

(Power Module) Total Current Control

(Over Current Protection) DC Peak Control Discharge Pipe Temp Control Low Ambient Function Oil Return Control Oil Equalizing Control

Cooling operation Heating operation Dry operation Cooling mode is automatically changed to heating mode and

vice verse Powerful cooling mode Powerful heating mode Air volume & set temp. are automatically selected for saving

energy in cooling mode Operation without remote controller After cooling operation, this function makes the evaporator

dry Indoor Fan speed Control Air volume control Program Vertical Airflow Direction control Air volume & set temp. are automatically changed for com-

fortable sleep When power returns after a power failure, Unit restarts in the

previous operating mode For noise prevention For overload prevention

To prevent cold wind blow on heating mode start Evaporator frost prevention To protect compressor To protect fan from accumulated ice at base panel Condenser frost prevention Over current prevention Modulation of voltage & frequency

To protect power module

To protect power device

To protect power module For overheating protection For operation at low temp. To protect compressor To protect compressor

Cooling Mode Only

9,12k Model Only

NOTE: The Exploded View SVC Manual has the particular Function table for each model.

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LGE Internal Use Only

Part 2 Functions & Controls

2. Basic Mode Controls

2.1 Cooling Mode

+0.5°C(1°F)

Setting Temp.

-0.5°C(-1°F)

INV. Comp. Frequency

High LowHigh

Low

Comp. OFF

Thermo ON

Thermo OFF

• Operating frequency of compressor depends on the load condition, like the difference between the room temp. and the set temp., frequency restrictions.

• If the compressor operates at some frequency, the operating frequency of compressor cannot be changed within 30 seconds. ( not emergency conditions)

• Compressor turned off when

- intake air temperature is in between ±0.5°C(±1°F) of the setting temp. limit for three minutes continuously.

- intake air temperature reaches below 1.0°C(2°F) of the temperature of setting temp..

• Compressors two minutes time delay.

- After compressor off, the compressor can restart minimum 2 minutes later.

2.2 Heating Mode

5˚C(9˚F)

Thermo OFF

2˚C(3.6˚F)

Setting

Temp.

INV. Comp. Frequency

High LowHigh Comp. OFF

Low

Comp. OFF

Thermo ON

• Operating frequency of compressor depend on the load condition, The difference between the room temp. and set temp., frequency restrictions.

• If compressor operates at some frequency, the operating frequency of compressor cannot be changed within 30 seconds.

• Condition of compressor turned off

- When intake air temperature reaches +5°C(9°F) above the setting temperature.

• Condition of compressor turned on

- When intake air temperature reaches +2°C(3.6°F) above the setting temperature.

* Condition of indoor fan turned off

- While in compressor on : indoor pipe temp. < 20°C(68°F)

- While in compressor off : indoor pipe temp. < 30°C(86°F)

• While in defrost control, the indoor and outdoor fans are turned off.

• Compressor 2minutes delay

- After compressor off, the compressor can restart minimum 2 minutes later.

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LGE Internal Use Only

Part 2 Functions & Controls

2.3 Healthy Dehumidification operation

• When the dehumidification operation is set by the remote controller, the intake air temperature is detected and the set-

ting temp. is automatically set according to the intake air temperature.

Intake air Temp. Setting Temp.

26°C(78.8

24°C(75.2

22°C(71.6

°F)

18°C(64.4°F) ≤ intake air temp. < 22°C(71.6

intake air temp. < 18°C(64.4

•

When intake air temp. is 1 C(2 F) above the setting temp., condition of compressor is same as in cooling mode operation.

°F)

≤ intake air temp. 25°C(77

≤ intake air temp.< 26°C(78.8

≤ intake air temp. < 24°C(75.2

°F)

°F) °F)

°F)

intake air temp. -1°C(-2

intake air temp. -0.5°C(-1

intake air temp.

18°C(64.4

°F)

• When intake air temperature reaches 1 C(2 F) below the setting temp., compressor operates in step1~step3 and the

indoor fan speed again operates at low speed or comes to a stop.

2.4 Auto changeover operation

• The air conditioner changes the operation mode automatically to keep indoor temperature steady.

• When room temperature vary over ±2°C(±4°F) with respect to setting temperature, air conditioner keeps the room tem-

perature in ±2°C(±4°F) with respect to setting temperature by changing the mode from cooling to heating and vice versa.

+4°C(+8°F) +2°C(+4°F)

+0.5°C(+1°F)

Setting

Temp.

-0.5°C(-1°F)

-2°C(-4°F)

Mode

Cooling operation

Heating operation

Switching point

Heating thermo off

Cooling thermo off

Switching point

Cooling operation

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LGE Internal Use Only

Part 2 Functions & Controls

3. Special Mode Controls

3.1 Jet Cool operation

• In the heating mode or Fuzzy operation, the Jet cool function does not work.

When it is input while in other mode of operation (cooling, dehumidification, ventilation), the Jet cool operation takes place.

• In the Jet cool mode, the indoor fan is operated at super-high speed for 30 min. at cooling mode operation.

• In the Jet cool mode, the room temperature is maintained at a setting temperature of 18°C(64.4°F).

• When the sleep timer mode is input during the Jet cool operation, the Jet cool mode has the priority.

• When the Jet cool button is pressed, the horizontal vane of the unit is reset to those of the initial cooling mode and

then operate so that the air outflow could reach further.

3.2 Jet Heat operation

• While in cooling mode or Fuzzy operation, the Jet Heat function does not work.

When it is input while in the Heating mode operation (dehumidification), the Jet Heat mode operation takes place

• In the Jet Heat mode, the indoor fan operated at super-high speed for 60 min. at Heating mode operation.

• In the Jet Heat mode, the room temperature is maintained at a temperature of 30°C(86°F).

• When the sleep timer mode is input during the Jet Heat mode operation, the Jet Heat mode has the priority.

• When the Jet Heat button is pressed, the horizontal vane of the unit is the unit reset to those of the initial Jet heating

mode and then operates so that the air outflow could reach under flow.

3.3 Energy saving operation in cooling mode

• During cooling and dehumidification mode of operation, the Energy saving button can be input.

• In this operation, before we feel cold the set temperature and air volume is set automatically to save energy.

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LGE Internal Use Only

Part 2 Functions & Controls

4. Utility Functions

4.1 Forced operation

• To operate the appliance manually in case when the remote control is lost, the forced operation selection switch is on

the main unit of the appliance, and operate the appliance in the standard conditions.

• The operating condition is set according to the outdoor temp. and intake air temperature as follows.

Indoor temp.

over 24°C(75.2°F)

21~24°C(69.8~75.2°F)

below 21°C(69.8°F)

Operating Mode

Cooling

Healthy Dehumidification

Heating

Setting temp.

22°C(71.6°F)

23°C(73.4°F)

24°C(75.2°F)

Setting speed of

indoor fan

High speed

• The unit select the last operation mode in 3 hours.

• Operating procedures when the remote control can't be used is as follows :

- The operation will be started if the ON/OFF button is pressed.

- If you want to stop operation, re-press the button.

- The ON/OFF switch is on the display PCB or side of indoor unit

4.2 Auto cleaning operation

• Function used to perform Self Cleaning to prevent the Unit from Fungus and bad odor.

• Used after the Cooling Operation before turning the unit off, clean the Evaporator and keep it dry for the next opera-

tion.

• The function is easy to operate as it is accessed through the Remote controller.

1) Heat/pump Model

ON

Cooling CYCLE

Comp.

Indoor Fan Setting Step LL LL LL

ON

OFF

13 Min

HeatingFan

60 Sec 120 Sec

ONOFF OFF

Fan

2) Cooling/only Model

ON

Comp.

Indoor Fan

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OFF

Cooling CYCLE

ON

Setting Step Low

LGE Internal Use Only

Fan

30 Min

OFF

Setting temp. (˚C)

1.0˚C(2˚F) up

Cooling ON temp. (Setting temp. +0.5˚C(+1˚F))

Cooling OFF temp. (Setting temp. -0.5˚C(-1˚F))

0.5 1 Sleep time (hour

)

Part 2 Functions & Controls

4.3 Air volume control

• Indoor fan motor control have 6 steps.

• Air volume is controlled "SH", "H", "Med", "Low" by the remote con-

troller.

• "LL" step is selected automatically in Hot start operation.

4.4 Natural Air Control(Auto Wind)

• When the Auto Step is selected and then operated, the high, medi-

um, or low speed of the airflow mode is operated for 2~15 sec. randomly by the Chaos Simulation.

Step Description

LL Very low, In heating mode

L Low M Med H High

SH Super high

Auto Natural wind

4.5 Chaos Swing

• By the Chaos swing key input, the horizontal vane automatically operates with the Chaos swing or it is fixed to the desired direction.

4.6 Sleep mode Auto control

• When the set sleep time is reached set time of [1,2,3,4,5,6,7hour] input by the remote control during the operation, the operation of the appliance stops.

• When the appliance is on pause, the sleep timer mode cannot be input.

4.6.1 Sleep timer operation for cooling cycle

• While in cooling mode , 30 min. after the start of the sleep timer, the setting temperature increases by 1 C(2 . After another 30minutes lapse, it increases again by 1°C(2 .

NOTE: Some Models are different by swing width and swing pattern.

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LGE Internal Use Only

Part 2 Functions & Controls

Setting temp. (°C)

Heating ON temp. (Setting temp)

Heating OFF temp. (Setting temp. +4.0°C(+8°F))

1 2 Sleep time (hr

)

1.0°C(2°F) down

4.6.2 Sleep timer operation for heating cycle

• While in heating mode, 60 min. after the start of the sleep timer, the setting temperature decreases by 1 C(2 . After another 60minutes lapse, it decreases again by 1°C(2 .

4.7 Auto restart

• When the power comes back after a sudden power failure during operation, the mode before the power failure is kept on the memory of the appliance and it automatically operates in the saved mode on the memory.

• Operation mode that is kept on the memory

- State of operation ON/OFF

- Operation mode/setting temp./selected airflow speed

- Sleep timer mode/remaining time of sleep timer

- Chaos Swing

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LGE Internal Use Only

Part 2 Functions & Controls

Comp. free

Comp. Step 4 Comp. Step 2

Comp. off

T1

3˚C(37.4˚F)

6˚C(42.8˚F)

7˚C(44.6˚F)

Indoor pipe temp.

5. Protection Functions & Controls

5.1 Five Seconds Stand-by (fan)

• The indoor unit fan rotates after 5 seconds when unit is turned on.

5.2 Two Minutes Stand-by (comp.)

• Compressor starts two minutes later, after it is turned off

5.3 Hot start

• When unit starts in the heating mode to prevent cold wind blowing, the indoor fan does not rotate until the temp. of heat exchanger reaches 30°C(86°F)(model by model)

5.4 Freeze prevention (Protection of the evaporator pipe from frosting)

• If the indoor pipe temperaure is below 0°C(32°F) in 7 min. after the compressor operates without pause while in cooling cycle operation mode, ➔ compressor, outdoor fan are turned off.

• When indoor pipe temp. is 7°C(44.6°F) or higher after 2 min pause of compressor ➔ compressor, outdoor fan is turned on according to the condition of the room temperature.

T1: 0 ~ 2°C(32~35.6°F)

NOTE: Some Models are different by T1.

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LGE Internal Use Only

Part 2 Functions & Controls

5.5 Compressor Preheating

5.5.1 9,12kBtu/h Model

With low outdoor temperature, It preheats the compressor to maintain the oil viscosity before the unit starts. Preheating Mode preheats the compressor motor coil by electric current without compressor running.

Mode-in conditions : Outdoor temp. < 0˚C (32˚F) and D-pipe temp. < 15˚C (59˚F) Mode-out conditions : Outdoor temp. > 5˚C (41˚F) or D-pipe temp. < 25˚C (77˚F) or Compressor on

5.5.2 18, 24, 30kBtu/h Model

When the unit starts with low outdoor temperature, It preheats the compressor to maintain the oil viscosity. If it is under the following conditions, the compressor runs with 15Hz for a specific time

Conditions : heat sink temperature < 0˚C (32˚F) and D-pipe temperature < 0˚C (32˚F)

Outdoor Temperature Running Time [sec]

-5˚C (23˚F) ~ -0˚C(32˚F) 90

-10˚C (14˚F) ~ -5˚C (23˚F) 180 Under -10˚C (14˚F) 300

5.6 Sump Heater Control (9, 12kBtu/h Model Only)

With low outdoor temperature, the sump heater located on base panel prevents icing that may cause drain blockage and fan damage.

Heater-on conditions : Outdoor temp. ≤ 0˚C (32˚F) and heating mode Heater-out conditions : Outdoor temp. > 1˚C (34˚F)

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LGE Internal Use Only

Part 2 Functions & Controls

5.5 Automatic defrost

5.5.1 9,12kBtu/h Model

• While in heating mode operation in order to protect the evaporator pipe of the outdoor unit from freezing, reversed to cooling cycle to defrost the evaporator pipe of the outdoor unit.

• Defrosting control is available 40 minutes later since heating cycle started and the difference of the pipe temperature of outdoor unit reaches above option 1.

• The defrosting control is available without reference to heating operation time only if the pipe temperature of outdoor unit reaches below option 2.

The mean outdoor temperature

The minimum Time of Heating(sec)

Minimum Time Of Heating

Operating

Setting Freq.

Freq. Of Comp (Comp off Inapplicable.)

Operating

Setting Freq.

Freq. Of Comp (Comp off Applicable.)

The Degree of Superheat

EEV

Control

Open step

4-Way

Indoor

ON

Setting Speed

FAN

Setting

Indoor

Speed

FAN

-10˚C(14˚F) less than

>4Option 1

And Heating operating time 40 minutes

5sec

Step 5

Min

15 sec

off

Step 5

Min

-5~0˚C(23~32˚F) between

Expected heating operating time

Main Deice time

30 sec

10 sec

300

OFF

Min

off

Min

off

Starting Step

Hi Speed

Hot

OFF

Start

1min

Step 3

ON

0˚C(32˚F) more than-10~-5˚C(14~23˚F) between

>5>5>5

-25-25-30-30Option 2

Setting Freq.

Setting Speed

Super low speed

° low speed

Pre-Heat LED

OFF

Deice STEP 0123456

Model (kBtu/h) Compressor Frequency EEV

9 65Hz(Step 5) 300

12 80Hz(Step 5) 300

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ON

OFF

LGE Internal Use Only

Part 2 Functions & Controls

5.5.2 18,24,30kBtu/h Model

• Starting to the defrosting operation

1) Defrost operation will be start when the conditions below are matched

a) Accumulation time of operation and the period after completion of defrost = 35 min.

b) After 10 minutes from re-starting the compressor .In case of being over 35 minutes of accumulated operating

time, defrosting operation starts after 10 minutes.

c) Piping temperature of the outdoor heat exchanger maintain below defrost starting temperature for 4 minutes

after 35 minutes continuous operation.

d)In case of passing 10 minutes after oil recovery operation

2) Outdoor piping temperature is below than –6°C (21.2°F, Option) for starting defrosting operation.

Defrosting

Comp. Freqency

Model (kBtu/h) Defrosting Comp. Frequency EEV

18 90Hz 350 24 77Hz 350 30 90Hz 350

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LGE Internal Use Only

Part 2 Functions & Controls

• Defrosting Control Algorithm

1) Lowering the compressor frequency when starts the defrosting operation.

Constant speed compressor is ON after 10 seconds from the arrival time of 30 Hz (Option) frequency and is speed up its revolution till 100 Hz (Option)

2) Every EEV have 350 pulse (Option) of opening when starts defrosting operation.

3) Reversing valve is OFF after 5 seconds from arriving the compressor operating frequency of 30 Hz and then fans of indoor units turn OFF.(including the indoor unit with being OFF except the remote controller is being OFF)

4) After 5 seconds from the time arriving 30 Hz, fans of outdoor unit turn OFF and Hot Gas bypass/Oil separator valve turn ON.

NOTE: Comp.frequency and EEV pulse is different each models.

• Control algorithm of defrost completion

1) Frequency of compressor lowering to 30 Hz and maintain constant speed operation with 30 Hz for 75 seconds and then stating operation. If the constant speed compressor is OFF, it will be receive OFF signal after 5 seconds from the arrival time of 30 Hz.

2) The EEV will open with the standard previous pulse after 5 seconds from the time of 30 Hz.

3) Reversing valve is ON after 15 seconds from the time of 30 Hz of compressor frequency.

4) Fan of outdoor unit is ON with high speed and maintain it after 5 seconds from the time of 30Hz.

5) Hot Gas bypass valve/Oil separator bypass valve make OFF after 75 seconds from the time of 30Hz.

NOTE: Comp.frequency and EEV pulse is different each models.

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LGE Internal Use Only

Part 2 Functions & Controls

3Ø Comp. Motor

U

UV W

V

W

+

5.6 Power Relay Control

• Power relay turns on 1 second later after the power is supplied to the outdoor unit.

• Control sequence : power on → PTC operating → power relay on

5.7 Inverter

1. The single phase power AC is converted into DC.

2. The single phase power DC is converted into a three phase chopped DC voltage with a variable frequency.

3. When the frequency changes, the rotation speed of the compressor changes resulting in an changed refrigerant circulation. This leads to changeable amount of the heat exchange per unit.

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LGE Internal Use Only

Lg Lan125hv Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual